This invention pertains to chromatography, specifically to radial flow chromatography, in which the flow is essentially in a radial direction in the sorbent bed, rather than in an axial direction.
Radial chromatography dates back at least to 1947 when Hopf, P., Ind. Eng. Chem., Vol.39, p. 938 (1947), invented the so-called chromatofuge for separating liquid solutes using centrifugal force. This device and its successors, such as Well, H., Canadian Chem. and Process Ind., November (1949); Mitchell, H. L., Schrenk, W. G., and Silker, R. E., Ind. and Eng. Chem., vol. 45, p. 415 (1953), were physically large and cumbersome, and were used primarily for preparative-scale separations. Heftmann, E., Krochta, J. M., and Farkas, D. F., J. Chrom., vol, 66, p. 365 (1972), reduced the size of the liquid separator, and also increased rotational speed to 1950 revolutions per minute.
The radial flow configuration for packed beds of particles is a recent enhancement procedure which has been used in chemical reactors, and which has been suggested generally as a possible mode for analytical chromatography. Rice, R. G., Chem. Eng. Sci., vol. 37, p. 83 (1982).
Liquid radial flow chromatography driven by a pressure drop across the separation medium has been discussed in references such as Saxena, U.S. Pat No. 4,627,918. Liquid radial flow in a thin separation medium similar to separation media used in thin layer chromatography has been discussed in references such as Andresen and Saxena, U.S. Pat. No. 4,708,782.
Yee, M., M. S. Thesis, Louisiana State University, Baton Rouge La. (1987), attempted gas radial flow chromatography, wherein pressure was used to drive gas through the chromatographic bed. Yee compressed the beds used, but was unable to achieve uniform radial flow. Uneven distribution of the fluid flow through the bed was a serious problem in Yee's results. Unless the radial flow of fluid can be made uniform, the technique's usefulness for separations, particularly analytical separations, is severely limited.